Centrifugal pump.



E. A. HANSEN.

CENIRIFUGAL PUMP.

APPLICATION FILED JUNE I2, I9I3.

1,143,957. Patented June 22, 1915.

EIGIL AAGE HANSEN, or duif-piensen,- DENMARK.

NTBIFUGA; Puur.

Specification of Letters Patent.

Appiication med :um 12,1618; serial No. 773,159:

`To all 'whom it may concern.'

Be it known that, I, EIGIL AAGE HAiisEN, subject of the King of Denmark, residing at Nordre F asanvej 32, Copenhagen, Denmark,

v,have invented certain new and useful Imrovements -in or. Relating to Centrifugal umps, of which the following is a specilication.

Thepresent invention relates to centrifugal pumps and has for its object to provide an improvedpump which may be used for the most varying purposes, but will be herein with reference to its employment as a mil pump. It is particularly suitable for this purpose inasmuch as it conveys the milk to the desired place withoutthe occurrence of any frothing. In order entirely to prevent frothing means musty ybe provided for permitting the excess f. of

air present in the liquid to leave fthe pump by an opening other than that by which the liquid is expelled so that the latter is not mixed with the air, when it leaves the pump. This end is attained according to this invention by causing the air to leave the pump at the pressure end. For this purpose a smallspace for the Aegress of the air may be provided Lbetween the shaft and the hole in the back cover, through which the shaft passes and whichis at'tle pressure end-of the pump body. VIf the pump is provided at this end with a stuffing box, the desired nd ma `be attained by boring out the shaft in the direction of its len h and. providingtransverse holes communicating iwith'the interior of vthc pump and with the hollow interior of the shaft, so that the interior of the pump is thereby put into communication with the atmosphere. 1 A When the liquid enters the body of the pump it is thrown with great force against.

the interior peripheral wall ofthe pump, the froth bubbles containing airburst and the air is then forced out into the atmosphere as hereinbefore mentioned. The liquid thus rendered free of air is then incapable of forming froth.

In order to avoid-'loss of liuuid through the air path, the Dump should be set in motion before the liquid is introduced. When the work is finished and the pump is to be put out of operation the liquid present in the pipe should be drawn off by a specialtap provided beneath it.

In the pumping both of milk and of other liquids there sometimes occur, however, othery disturbances in connection with which the Patented June 2.3; 191th present invention is of importance-as for,"H

instance, when the flow Ainto the pump, for example through its feed pipe is irregular. Provided that no more liquid r-uns down into the `feed pipe than can flow quickly into the pump, there will be no disadvantageous 0ccurrences since in this case any air, which may be present with the liquid finds a free return path again into the feed pipe. When however the inflow is so rapid that the feed pipe is filled, the air cannot get back into the atmosphere and the pump ceases to work satisfactorily. The liquid in the feed pipe flows back, after which the pump again takes up some of it, the liquid runs back again, and so on. These disturbances, which occur with all centrifugalv pumps, are en-l tirely eliminated Aby the arrangement herein described. e e

The invention is illustrated in the accompanying drawing showing a sectional view of an apparatus embodying the invention.

The driving shaft f carries belt pulleys g and runs in bearings h in the frame work of the drawing on the left-hand side projects into the body of the pump and carries the impeller which is fastened thereto at` its broad end and runs in a conical two-part casing vformed by the conical fore part a and the back cover b. The conical fore part a is closed at the wider or pressure end by the back cover b, through which passes the shaft f.

It will be noted that the shaft is bored out longitudinally at z' and transverse holes e are provided which communicate therewith and with the interior of the pump body.

1. A centrifugal pump comprising a pump body, a shaft carrying an impeller adapted to rotate in the said body and means arranged at the pressure end of the pump whereby the interior of the said body is in the pump with the outer atmosphere.

2. A centrifugal pump comprising a pump body, a longitudinally bored shaft, and an impeller carried by said shaft and adapted `to rotate in the said body, said shaft con- 3. Acentrfugal pump oomprisinga pump In testimony whereof I have axed my bodly, a longitdinaly lloed slaft, an imsignature in presence of two witnesses.

el er carried y sai 's a t an adapted to otate in the said body, said shaft having a. EIGIL AAGE HANSEN' 5 plurality of holes connecting the interior of Witnesses:

the pressure end of the pump with the bore VIGGO BLOM, of the shaft. .G. STB. 

